Switch mode power supplies (SMPSs) are used in many electrical devices to receive electrical energy with one set of parameters (e.g., from a power source) and transform and regulate the received electrical energy to another set of parameters, typically for use by other components of the electrical devices. For example, SMPSs can be used to perform DC-to-DC power conversion in both stepping up and stepping-down an input voltage.
Some SMPS implementations use a controller circuit to control the activation of the switch used to regulate the output voltage of the SMPS. Typical controller implementations include an oscillator frequency for timing and control functions of the SMPS. In some implementations, the oscillator is user-programmable by providing a mechanism for the user to connect circuitry (e.g., a resistor) to the control circuitry of the oscillator. Further, in some applications, it is desirable to synchronize the oscillator output signal(s) with a system or master clock signal of the SMPS.